More and more content is being delivered in digital form, and more and more digital content is being delivered online over private and public networks, such as Intranets, the Internet and cable TV networks. For a client, digital form allows more sophisticated content, while online delivery improves timeliness and convenience. For a publisher, digital content also reduces delivery costs. Unfortunately, these worthwhile attributes are often outweighed in the minds of publishers by the corresponding disadvantage that online information delivery makes it relatively easy to obtain pristine digital content and to pirate the content at the expense and harm of the publisher.
To prevent their content from being stolen or misused, content providers will download content only to trusted software, and therefore only to subscriber computers that can prove that the software executing on the subscriber computer is trusted. This trust concept is predicated on having a trusted operating system executing on the computer, which, by its nature, only loads trusted components and provides some kind of secure storage. The problem then becomes one of identifying an operating system with such peculiarity that the content provider can make an intelligent decision whether to trust its content to the operating system.
The related application titled “System and Method for Authenticating an Operating System to a Central Processing Unit, Providing the CPU/OS with Secure Storage, and Authenticating the CPU/OS to a Third Party” discloses one embodiment of a unique operating system identifier that is a cryptographic digest of all the software components loaded by the operating system. However, computers contain a myriad different hardware components, and the corresponding supporting software components are frequently updated to add enhancements and fix problems, resulting in a virtually unlimited number of operating system identities. While the content provider can maintain a list of those identities it trusts, or delegate the maintenance of such a list to a third-party, what is needed in the art is a way to reduce the number of trusted operating system identities without limiting the choices of software components available to a user.